Hoist



June 23, 1970 J, POMAGALSKl EVAL 3,516,642

HoIsT Filed Deo. 11. 1967 3 sheets-sheet 1 -Fic 5.

June 23, 1970 J, POMAGALSK| ETAL 3,516,642

HOIST 3 Sheets-Sheet 2 Filed Dec. l1, 1967 June 23, 1970 v J, PoMAGALSKl E IAL 3,516,642

HOIST Filed Dec. 11. 1967 3 Sheets-Sheet 3 United States Patent O 3,516,642 HOIST `lean Pomagalski, La Tronche, and Marcel Durand, Grenoble, France, assignors to Jean Pomagalski S.A.

Filed Dec. 11, 1967, Ser. No. 689,577 Claims priority, application France, Dec. 28, 1966,

Int. C1. Bead 1/28 U.S. Cl. 254-167 2 Claims ABSTRACT F THE DISCLOSURE A hoist with a frame in which is so tted that it may rot-ate a pulley with a groove for driving a cable passing in the groove, the slack side of the said cable being pressed into this groove by a compression wheel the axle of rotation of which is carried by a lever freely pivoting around an axle carried by the frame, this lever carrying a component so arranged as to be engaged by the traction side of the said cable to pull the said lever in response to the action of the load side of the said cable in a direction provoking the penetration of the said compression wheel in the said groove.

The invention relates to hoists or winches with a rotary grooved pulley for the driving of a cable passing in the groove and pressed into it by a compression wheel on a lever, pivoting on the frame of the hoist, and the fixed position of which is adjustable.

The invention may also be considered as relating to winches of the type indicated in which a component engages the traction side of the said cable, to pull the said levier under the influence of the load connected to the said traction side in a direction which indirectly causes the said compression Wheel to penetrate into the said groove.

It contributes to radial compression of the cable in the groove itself, which obviates the necessity for providing some means of holding at the bottom or on the flanks of the groove, which always more or less damages the cable sooner or later.

It has a component subjected to the load, and therefore proportional to the load, an advantage which is not offered by devices which directly compress the cable into the groove.

Finally, the invention offers other advantages, amongst which in particular are those of permitting a method of realization in which the compression force due to the load may be multiplied, of permitting a method of realization which guides the loaded side of the cable without any necessity for an auxiliary pulley, of permitting the guiding of the loaded side of the cable with bearing friction instead of slipping friction.

A method of application of the invention will now be described, as a non-limitative example, with reference to the annexed drawing, in which:

FIG. l represents schematically along an axial section a winch equipped with a compression device according to the invention, the winch being under load and the compression device in the active position;

FIG. 2 is a partial section on a larger scale than FIG. 1 showing the invented compression device in the inactive position;

FIG. 3 is a section analogous with that of FIG. 2 along line III-III of FIG. 4, the compression device being in the active position;

FIG. 4 is a section along line IV-IV of FIG. 3;

FIG. 5 is a section analogous with that of FIG. 3 illustrating a modified mechanism;

FIG. -6 is a section along line 'VI-VI of FIG. 5.

On these figures a yoke-shaped frame 10 may be hung 3,516,642 Patented June 23, 1970 or fixed by means of a hook 12 articulated on frame 10 on a horizontal axle 42, in the suspended position of the frame.

A V-grooved pulley 14 can turn freely around an axle 16 xed on frame 10, and can be operated in any manner. The two flanks of the V-groove may for example be provided with notches 18, 18', on which act a locking or holding pawl 20 articulated at 21 on frame 10 and an operating pawl 22 articulated at 23 on an operating lever 24 partially represented in FIG. 1 and which pivots freely on axle 16.

The pawls 20, 22 are subjected in the usual way to the action of springs, not shown, which tend to make their ends penetrate into notches 18, 18'. A compression Wheel 26 can turn freely on an axle 28 carried by a yoke 30 which is fitted so as to rotate on an axle 32 rigidly fixed on frame 10, axles 28 and 32 being at about the same distance from axle 16, to permit wheel 26 to exert compression in a radial direction. Yoke 30 is constituted of two parallel side-plates 31, 31', between which the two parts 38', 38" of a cable 38 engaged in the groove of pulley 14, and pressed into this groove by wheel 26 can pass. Yoke 30 has a second wheel 34 articulated between the two side-plates 31, 31', and loose fitted on an axle 36, parallel with articulation axle 32 of yoke 30 on the frame and with axle 28 of compression wheel 26, and therefore with the plane containing these two axles, but not located within the plane. Lever arm 36-32 is much greater than 28-32, in order to permit multiplication of the effort. This second wheel 34 is engaged by the traction end 38' of the cable to which is attached the load, not shown. It thus has a triple function: it directs the loaded side 38' of the cable in such a manner that axle 42, the points of contact of the cable on the pulley 14 and on wheel 34 tend to be in a straight line. In this limit position the compression wheel does not press the cable to the bottom of the groove, and the adherence is ensured by the flanks of the groove. In addition the guiding of the loaded end of the cable is by running friction and not by slipping, and during the pivoting of yoke 30 around its articulation axle 32, compression wheel 26 engages in the groove of pulley 14 or withdraws from it while compressing or releasing the slack end 38" of the cable engaged in the groove of pulley 14 and passing between this pulley and compression wheel 26. The degree of pivoting of yoke 30 in relation to frame 10 is determined by the position of wheel 34 on which rests the traction end 38 of the cable and thus depends on the position of this end in relation to frame 10. In the position illustrated in FIG. 2, this end 38' is not under tension and yoke 30 can then be pivoted freely, the only forces to be overcome being those of friction and of the stiffness of the cable. In the position illustrated in FIG. 3, this end 38' is under tension, and the position of yoke 30 is then perfectly defined.

The device functions in the following manner:

Frame 10 is attached by its hook 12 to a xed point, and cable 38 is slid through yoke 30 of the compression device, between wheels 26 and 34 then inside the groove of pulley 14, `while care is taken that the slack end 38 passes between compression wheel 26 and the groove of pulley 14. The insertion of cable 38 is easily accomplished, yoke 30 not being pulled by the springs against grooved sheave 14. At long as cable 38 is not under tension, compression wheel 26 is not engaged in the groove of pulley 14 (position shown in FIG. 2) and the length of the cable can easily be adjusted by simple sliding of the cable in the groove. A load having been xed to end 38 of the cable, this may now be hauled by turning pulley 14 in a well-known manner by means of operating lever 24 and pawls 20 and 22. As soon as tension is exerted on the taut end 38' the winch takes up an inclined position, shown in FIG. 1, so as to align fixing point 42 of the winch with taut end 38' of the cable. This inclination is perfectly deined by the design dimensions of the winch, in particular by the diameter of the edge of the groove of pulley 14 and the distance between ixing point 42 and axle 16. This inclination of the winch and frame in relation to the direction of application of the load implies 'a predetermined distance between articulation axle 32 of the compression device and wheel 34 coacting with the taut side 38 of the cable and arising from this a well-defined position of yoke 30 in relation to frame 10 (position shown in FIG. 3) in which com pression wheel 26 is engaged in the groove of pulley 14.

The slack side 38 of the cable is therefore pressed into the groove of pulley 14 by a stress provided by the tension in the taut side 38 of the cable. The degree of penetration by the compression wheel will be determined in such a manner as to ensure perfect adherence of the cable 38 in the groove of pulley 14 for the entire range of eiforts for which the winch is designed. The compression stress may be modified by changing, for example, the relative positions of axles 28, 32 and 36. As soon as tension in cable 38 disappears yoke 30` is freed and slack end 38 of the cable may free itself from grooved pulley 14 (refer to FIG. 2). This compression device of particularly simple and robust construction may be advantageously applied to all types of winch using the grooved pulley, in particular to apparatus described in French Pat. No. 1,394,855 iiled on Feb. 22, 1964, whatever may be the operating means employed, for instance by a crank, a ratchet lever, a motor, etc. Yoke 30 of the compression device serves at the same time as a guide for the taut and slack sides of cable 38, and any other guide device is thus superuous.

FIGS. 5 and 6 are views analogous to FIGS. 3 and 4, respectively, and illustrate a modified compression mechanism, in which the distance between the axle 32 and the center of the shaft 28 is lower than the radius of the Wheel 26. This wheel 26 is rot-atively mounted on a shaft 28 arranged as a discus fixed and locked by a pin 40 on the side plates 31, 31. The lever arm 26, 32 may be notably reduced and made as little as desired.

What we claim is:

1. In a hoist mechanism, an elongated frame member, hook means attached to the upper end of said member for swingably supporting said member, a pulley rotatably mounted on said member and having flanges deiining a V-shaped channel, rachet and lever means pivotally mounted on said member for rotating said pulley in one direction for hoisting a load, a cable passing around said pulley and having a tension end which is attached to the load and a slack end, a yoke p-ivotally mounted on a lower end portion of said member adjacent the periphery of said pulley, a pressure wheel rotatably mounted on said yoke adjacent the periphery of said pulley and in position to press the slack end of said cable into said V-shaped channel of said pulley, and a guide wheelv rotatably mounted on said yoke at a distance from said pressure wheel and from the pivot of said yoke and in position to be engaged by the tension end of said cable to swing said yoke about its pivot and thereby press said pressure wheel in against the slack end of said cable to inhibit slipping of said cable on said pulley when the cable is under tension, said yoke comprising a triangular plate with the pivot of said yoke located at one corner of the plate, said guide wheel mounted at the opposite corner and said pressure wheel mounted on the side opposite said guide wheel, the distance of the axis of said guide wheel from the pivot of said yoke being greater than the distance of the axis of said pressure wheel from said pivot so that the force applied by said pressure wheel to the slack end of said cable is a multiple of the force applied by the tension end of said cable to said guide roller.

2. A hoist according to claim 1, in which said yoke comprises two spaced parallel triangular plates between which said pressure Wheel and guide Wheel are rotatably mounted and between which said cable passes and is guided.

References Cited UNITED STATES PATENTS HARVEY C. HORNSBY, Primary Examiner U.S. Cl. X.R. 

